text: Research International produces and sells the TacBio particle detection system. The system samples the air continuously and monitors for  aerosol particle or bio-particle levels
  It does not identify the type of bio-particle detected but will notify the mailroom attendant if either excess particles or bio-particles are present. This is an early warning system that gives the mailroom supervisor enough time to notice a potential threat and to test for biological agents or airborne threats before mail is delivered to a recipient.